Crepe yarn



Patented July 21, 1942 FFiCE canra YARN George Schneider, Montclair, N. 1., assignor to Celanese Corporation of America, a corporation of Delaware No Drawing. Application October 25, 1940, Serial No. 362,801

1 Claim.

This invention relates to the production of crepe yarns and fabrics, and relates more particularly to the production of crepe yarns and fabrics made of or containing synthetic linear polyamide condensation products.

An object of my invention is the production of yarns containing at least some synthetic linear polyamide condensation products having a high degree of twist and suitable for the production of crepe fabrics.

Another object of my invention is to treat said yarns containing at least some synthetic linear polyamide condensation products in such a manner as to produce fabrics of uniform creping property.

A further object of my invention is to produce crepe yarns that shrink and buckle in a very short period of time when immersed in a heated creping bath.

Other objects of my invention will appear. from the following detailed description.

Textile materials made of or containing yarns, filaments or fibers of synthetic linear polyamide condensation products find an extensive use. The fabrics made therefrom are not only decorative but are strong, wear well and have desirable elastic properties. Numerous types of fabrics have been made in whole or in part of these synthetic linear polyamide condensation products and among these fabrics are various types of knitted and woven materials. While it is possible to duplicate a large number of known fabric types using yarns of synthetic linear polyamide condensation products not all fabric types could be satisfactorily produced.

I have now discovered that if yarns of synthetic linear polyamide condensation products are highly twisted, especially in the presence of steam, these yarns may be woven into fabrics comprising in whole or in part of said yarns to produce a fabric possessing a substantial amount of crepe.

The synthetic linear condensation polymers suitable in my process may be compounds such as the polyamides derived from amino-acids or polyamides derived from the condensation products of diamines with dicarboxylic acids.

The polyamides may be deriver from diamines of the formula NH2CH2RCH2NH2 and dicarboxylic acids of the formula HOOCCHaR'CHaCOOH or their amide-forming derivatives, in which R and R are divalent hydrocarbon radicals -free from olefinic and acetylenic unsaturation and in which R has a chain length of at least two car- R is (CH2)1I where a: and yare integers and wherein .r is at least two. As examples of polyamides which fall within one or both of these groups might be mentioned polytetramethylene adipamide, polytetramethylene suberamide, polytetramethylene sebacamide, polypentamethylene adipamide, polvpentamethylene sebacamide, polypentamethylene suberamide, polyhexamethylene suberamide, polyhexamethylene sebacamide, polyhexamethylene adipamide, polyoctamethylene adipamide, polydecamethylene adipamide, polydecamethylene p-phenylene diacetamide, and poly-p-xylylene sebacamide. Instead of the use of polyamides of the diamine-dibasic acid type, those prepared from polymerizable monoaminomono-carboxylic acids, for example G-amino-caproic acid or 9-amino-nonanoic acid, or their amide-forming derivatives may be used.

The fibers or filaments may be made by spinning the above mentioned polymers into filaments and then subjecting the fibers or filaments to stress to obtain an oriented molecular structure.

The threads or yarns may consist of substantially continuous filaments of the synthetic linear polyamide condensation products or they may contain discontinuous filaments or fibers. The length of the discontinuous filament or fibers may vary within wide limits. When discontinuous filaments or fibers are employed they may be formed into yarns by spinning on either the cotton, wool or silk spinning systems or yarns of discontinuous filaments may be made by breaking or cutting yarns or bundles of continuous filaments along the length of the yarn or bundle in such a manner that only a few filaments are severed at any one point in the yarn. The conversion of continuous filament yarns into discontinuous continuous filament yarnin this manner is known in the art as staplizing. While the yarns may be made wholly of synthetic linear polyamide condensation products, the yarns may also contain filaments and/or fibers of other materials such as wool, cotton, silk, regenerated cellulose or organic derivatives of cellulose. These materials may be incorporated by doubling a yarn which contains synthetic linear polyamide condensation products with one or more yarns of cotton, wool, silk, regenerated cellulose or organic derivatives of cellulose.

In ca y out my process, twisting may be effected on a device of the kind in which the thread is drawn on over the end of a rotating package through a guide fixed preferably substantially in line with the axis of rotation of the bon atoms, particularly when R is (CHEM: and package and is thereafter wound on a bobbin or the like, the thread being passed, on its way from the guide to the bobbin, through steam. In this way the thread is subjected to the action of the steam during the actual application of a substantial amount of the twist, or to the action of both steam and moisture if it ispassed through steam under such conditions that moisture is present. However, any other suitable crepe twisting device may be employed-in conjunction with steaming. For example, a ring twister may be used for the crepe twisting of the yarn. It is preferable that the twisting mechanism, the thread guides, the supply package, the take-up package and the steaming device be so arranged that the twist resulting from the rotation of the package or twisting mechanism is atleast partly inserted while the thread is under the influence of steam. Thus, if desired, the twist may 'be inserted in the yarn in a plurality of stages with a portion of the twist being inserted at one point and the remainder at another with the yarn sub- The highly twisted crepe threads of synthetic linear polyamide condensation products may be incorporated in the fabrics in various ways, for example, the weft alone may be wholly or partially composed of such threads or the warp may also contain them. Valuable fabrics may be produced by employing in the warp, threads of relatively low twist and in the weft both. crepe threads having a left hand twist and crepe threads having a right hand twist, pairs of ,threads of left hand twist alternating with pairs of threads of right hand twist.

Fabrics containing highly twisted crepe threads prepared in accordance with my invention may be scoured in the manner employed in connecjected to the action of steam and moisture at either stage but at least in the final stage.

Steaming may conveniently be effected by a1- lowing the thread to pass through a suitable chamber supplied with steam, preferably under such conditions that moisture is present. The chamber may be provided [with small holes, top and bottom, to permit of passageof the thread, and also with a steam inlet. The size of the chamber should be sufiicient to afford the thread the requisite length of travel in the steam. Alternatively, a chamber having a smaller diameter may be used, in which case the chamber may be provided with hollow nipples communicating therewith and through which the yarn passes, the nipples being of sufficient size to provide, together with the size of the chamber, the requisite length of travel in the steam.

The presence of the desired moisture may be assured by supplying wet steam to the steaming device and/or by arranging for the condensation of steam to supply the requisite moisture. Wet steam may be conveniently produced by passing steam through water at suitable velocity, for instance, small traps for condensed water may be provided at suitable intervals in the steamin chamber and steam injected therethrough by means of small pipes or orifices. Another method of ensuring the presence of moisture is to wet the thread with water. For example, the bobbins of thread may be wetted before the twisting operation or, better, water may be applied to the thread by means of wick or other device after the thread leaves the spindle and prior to its entering the steaming device.

Steam at slightly above atmospheric pressure, or at a pressure of 1 or more millimeters of water, is most conveniently employed. If desired, however, the steaming may be effected with steam at any desired super-atmospheric pressures, e. g., steam at 10-25 lbs. per square inch.

A steaming treatment of relatively short duration, such as may be secured by passing the yarn at a speed of from 2 to 10 meters per minute through, say, from 1" to 3" of steam, has been found to give satisfactory results. Lengthier treatments may, however, be employed, for example, the yarn may be passed at the said speeds through 6" to 12" or more of steam.

tion with fabrics comprising highly twisted yarns of natural silk or yarns of organic derivatives of cellulose such as cellulose acetate. Enhanced crepe effects may be obtained by employing a scouring or other aqueous crepe bath at or near the boiling point thereof. The fabrics made in accordance with my invention may be caused to crepe by immersing the same in -a bath maintained at about C. to C. and containing up to 10 grams Or more per liter of-soap. The length of treatment in the heated bath may be from 20 to minutes.

In order further to illustrate my invention, but without being limited thereto, the following example is given:

Example Yarn of 162 denier containing 69 filaments and made of a synthetic linear polyamide condensation product, which is sold under the name of Ny1on" is twisted to 70 turns per inch in steam at 93 C. This yarn is woven into a fabric in which the warp is a, 100 denier, 40 filament, 5 turns per inch dull cellulose acetate yarn and the weft or filling is the above twisted Nylon yarn. The fabric is then treated for 25 minutes in an aqueous bath maintained at 98 C. The fabric produced has a heavy and uniform crepe figure thereon which is substantially free from further shrinkage upon treatment in aqueous or other cleaning baths normally met with in the use of the fabric.

It is to be understood that the foregoing detailed description is merely given by way of iilustration and that many variations may be made therein without departing from the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patent is:

Process for the production of crepe fabrics concondensation product, which comprises steaming threads of filaments of a synthetic linear polyamide condensation product with steam at 93 C. under such conditions that moisture is present, twisting said threads to 70 turns per inch while the threads are subjected to the action of the steam, weaving said threads into a fabric and treating said fabric for 25 minutes in an aqueous bath maintained at 98 C., whereby a heavy and uniform crepe figure is produced on said fabric.

GEORGE SCHNEIDER.

taining threads of a synthetic linear polyamide 

